The present invention relates to a high-speed and high-port-density network routing apparatus and, more particularly, to a network routing apparatus in which the combination rate between connectible search engines and transfer engines can be changed to hereby achieve single-to-multiple, multiple-to-single, and multiple-to-multiple configurations.
In a network system, a plurality of networks are connected via a network routing apparatus such as a router, and packets are routed in the network routing apparatus. The network routing apparatus, after receiving a packet, determines the forwarding destination of the received packet from the destination address included in this packet, and then outputs the packet to the line to which the router or host or client terminal of the forwarding destination is connected.
An example of such a network routing apparatus is disclosed in, for instance, U.S. Patent Application Publication No. 20020027917 (Japanese Patent Laid-open No. 2001-211203). The network routing apparatus described in this Japanese Patent laid-open No. 2001-211203 comprises network interface boards (NIFS) that are each connected to various types of network interfaces (lines) to send and receive packets, routing processors (RPs) that search for the appropriate packet forwarding destination from the destination address included in the header of a received packet and then forward the packet, and a crossbar switch (CSW) that is connected to each RP to forward packets between RPs. In this conventional network routing apparatus, each RP further includes a plurality of packet forwarding units, each of which searches for the appropriate packet forwarding destination from the destination address included in the header of a received packet and then forwards the packet. In each RP, the received packet from an NIF and the received packet from the CSW are distributed to the above-mentioned plurality of packet forwarding units. Thus, the packet forwarding process in the network routing apparatus is speeded up.